JSFiddle - React, Tailwind, and code Playground
HTML
<select id='ItemType'>
<optgroup label="Florida Atlantic University">
<option value="1">Text</option>
<option value="2">Text</option>
<option value="3">Text</option>
</optgroup>
<optgroup label="Florida Tech">
<option value="4">Text</option>
<option value="5">Text</option>
<option value="6">Text</option>
</optgroup>
</select>
JavaScript
$('ItemType).filter('[optgroup[label*="' + itemgroup + '"]');